Misc. Functions

#include <dplx/cncr/misc.hpp>
namespace dplx::cncr {}

template<std::size_t N, typename T>
consteval auto make_byte_array(std::initializer_list<T> vs, T dv) noexcept -> std::array<std::byte, N>

Casts every provided value to std::byte and returns a brace initialized array with the results.

Parameters:

T dv – a default value which is used in case of vs.size() < N

Returns:

A byte array filled with the provided values.

template<typename R, std::size_t N, typename Fn, typename ...Args>
constexpr auto sequence_init(Fn &&initFn, Args&&... args) -> R

The return object is brace initialized by the results of N invocations of std::invoke(initFn, args..., cncr::mp_size_t<n>{}) where n is the current counter value starting at 0.

This helper function is mainly useful for constexpr initializing complex array class members:

struct chunk_cfg;
struct data_chunk
{
    data_chunk() = delete;
    explicit constexpr data_chunk(const chunk_cfg &cfg);
};
template <std::size_t N>
class data_container
{
    using chunks_type = std::array<data_chunk, N>;
    chunks_type chunks;
    static constexpr data_chunk init_chunk(const chunk_cfg &cfg, [[maybe_unused]] std::size_t n)
    {
        return data_chunk(cfg);
    }
public:
    constexpr data_container(const chunk_cfg &cfg)
        : chunks(dplx::cncr::sequence_init<chunks_type, N>(init_chunk, cfg))
    {
    }
}

template<typename R, typename Fx, typename ...Args>
constexpr auto sequence_init(Fx &&initFn, Args&&... args) -> R

Invokes template <typename R, std::size_t N, typename Fn, typename... Args> sequence_init() with N = std::size(R{}).